Utjecaj omjera izvora ugljika i dušika u podlozi na proizvodnju lipida u kvascu Trichosporon oleaginosus

master's thesis

• Title (english): Influence of the carbon to nitrogen source ratio in the medium on lipid production with yeast Trichosporon oleaginosus
• Author: Ena Miškulin
• Mentor: Mirela Ivančić - Šantek (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology); Zagreb
• Defense date and country: 2014-07-25, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Proveden je kontinuirani uzgoj kvasca Trichosporon oleaginosus s podlogom za prihranu koja je sadržavala glukozu kao izvor ugljika i amonijev klorid kao izvor dušika. Proučavan je utjecaj omjera ugljika i dušika (C/N, g g-1) u podlozi za prihranu na koncentraciju biomase i udjele proteina i lipida u stanici pri konstantnoj brzini rasta (D = 0,1 h-1). Na osnovu potrošnje supstrata i sastava stanice uočena su tri karakteristična tipa rasta. Pri malim omjerima C/N (≤ 15 g g-1) rast stanice limitiran je izvorom ugljika, dok je izvor dušika u suvišku (visoki udjel proteina i mali udjel lipida u stanici). Pri uzgoju s podlogom za prihranu sastava 15 g g-1 < C/N ≤ 46 g g-1, izvor dušika i ugljika bio je potpuno utrošen. Tijekom limitacije rasta s dva supstrata udjel proteina u stanici se smanjio, dok se udjel lipida povećao. Daljnjim povećanjem omjera C/N iznad 46 g g-1 dolazi do limitacije rasta stanica izvorom dušika, dok koncentracija izvora ugljika raste iznad 1 g L-1 (mali udjel proteina i veliki udjel lipida). Tijekom limitacije rasta izvorom dušika uz omjer C/N 153 g g-1 postignut je najveći prinos lipida od 0,27 g g-1 i najveća specifična brzina sinteze lipida od 0,0998 g g-1 h-1.

Abstract (english)

The oleaginous yeast Trichosporon oleaginosus was grown in continuous culture with feed medium containing glucose as carbon source and ammonium chloride as nitrogen source. The influence of the carbon : nitrogen ratio (C/N, g g-1) of feed medium on biomass concentration and protein and lipid content in the cell was studied at a constant growth rate (D = 0,1 h-1). On the basis of substrates utilisation and cell composition three characteristic growth paths were observed. At low C/N ratio (≤15 g g-1) cell growth was carbon-limited and nitrogen source was present in excess (high protein and low lipid content in cell). Growth with a medium of 15 g g-1 < C/N ≤ 46 g g-1resulted in complete utilisation of nitrogen and carbon source in the medium. During double-substrate limited growth, protein content was reduced while lipid content was increased. Further increase of C/N ratio resulted in nitrogen-limited growth, while carbon source concentration increased above 1 g L-1 (low protein and high lipid content). Under nitrogen limitation at the C/N ratio of 153 g g-1, the highest lipid yield of 0,27 g g-1 and the highest specific lipid formation rate of 0,0998 g g-1 h-1was observed.

• Keywords: oleaginozni mikroorganizmi; kontinuirani uzgoj; mikrobni lipidi; Trichosporon oleaginosus; biodizel
• Keywords (english): oleaginous microorganisms; continuous cultivation; microbial lipids; Trichosporon oleaginosus; biodiesel
• Language: croatian
• URN:NBN: urn:nbn:hr:159:096138
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-04-28 11:55:11